class_docstr: Gym Dictionary with arbitrary keys updatable after instantiation
  
  Example:
     space = FlexDict({})
     space['key'] = spaces.Box(4,)
  See also: documentation for gym.spaces.Dict
code: def __repr__(self):
      return (
          "FlexDict("
          + ", ".join(
              [str(k) + ":" + str(s) for k, s in self.spaces.items()]
          )
          + ")"
      )
  
file_path: ray/rllib/utils/spaces/flexdict.py
imports: import gymnasium
  from ray.rllib.utils.annotations import PublicAPI
label_desc: Use image node_id 6 for calling the FlexDict obj's underlying member method code with example usage: obj.__repr__() and returns: unknown